1. Field of Invention
This invention generally relates to eyelid covers, specifically to such eyelid covers that help block light from entering the eye by way of the eyelid to aid in sleep.
2. Prior Art
Light entering the eye through the eyelid can either be a nuisance or can even cause damage to the retina (for example when sunbathing). Light that enters the eye through a closed eyelid while sleeping can disrupt sleep patterns (for example when someone wants to sleep until after the sun has risen, but is bothered by ambient light entering through opaque curtains in the bedroom, which causes the individual to inadvertently awaken). Previously, various means of light occluding methods have been used to block unwanted light from entering the eye through the eyelid. Methods have included sleep masks that cover both eyes and have some sort of retention device, eyelid covers that are self-adherent or have a retention device, and light occluding curtain backings. These light occluding methods have served a number of end functions including medical eye exams, therapy for specific eye disorders, sunbathing, and sleep aids. However, all of these previous methods tend to have drawbacks including that they are 1) uncomfortable to wear, 2) are not easy to wear, 3) impede normal vision when in use, and 4) specifically related to sleep aids, disrupt sleep by unintended effects of their use.
Related to sleep aids, various forms of light occluding inventions have been made. For example, U.S. Pat. No. 5,741,582 to Leaderman and Fradin (1998) invented light occluding curtains that can be used in conjunction with normal draperies to help block out unwanted light to aid in sleep. These curtains are expensive to manufacture, are heavy, and significantly distort the normal look of draperies (for example, all light is blocked causing an overly dark look to a room during the day when a more diffuse light coming through a curtain may be desirable). Another problem with light occlusive curtains is that they must be used in every room where one wants to sleep, this may be inhibitive when sleeping in multiple rooms or traveling.
One inadequate solution to the above problems relates to light occlusive devices that are worn on the body, either as a sleep mask or as an eyelid cover. These devices solve the problem of traveling to other areas where light blocking curtains are not installed; but unfortunately, these worn devices cause other problems such as discomfort, interruption of normal sleep patterns, and interference with normal vision. U.S. Pat. No. 6,543,056 to Spiteri (2003) describes a modified sleep mask that purports to be an improvement on traditional sleep masks. Also, U.S. Pat. No. 4,872,217 to Kitayama (1989) describes an invention that is worn as a sleep mask to block light from entering the eye through the eyelid. Although this invention purports to be an improvement due to its ability to not contact the eyelid, this invention shares the same drawbacks of all sleep masks. Namely, the drawbacks of sleep masks include: 1) interference with normal sight (for example, the sleep mask must be manually removed to see clearly) and 2) the sleep mask contacts some part of the face or head of the wearer. These contact points are likely to become sleep disruptive pressure points, when the weight of the wearer's head sandwiches the sleep mask between the pillow and the wearer's face or eyes. Further, since sleep masks interfere with sight, they can create a claustrophobic feeling for the wearer, which is exacerbated by a potential need to remove the sleep mask rapidly while the wearer is in a somnolent state.
A continual problem for light occlusive sleep masks and eyelid covers is this need to remove the invention before one can obtain normal sight. For some inventions this is not a huge problem since their usage is in light occlusive therapy (in light occlusive therapy there is a strict amount of time that the devices are worn where during the wear-time the function is to block all or most light from entering the eye). For example see U.S. Pat. No. 4,944,040 to Riedel and Olsen (1990); U.S. Pat. No. 5,191,897 to Meshel (1993); and U.S. Pat. No. 4,951,658 to Morgan and Wyszynski (1989). However, most eyelid covers that have been invented that block light from entering the eye through the eyelid suffer from this problem of need for removal or manipulation in order for the wearer to see normally. For example see U.S. Pat. No. 5,191,897 to Meshel (1993) and U.S. Pat. No. 4,599,746 to Stoner (1986). The one known exception to this problem relates to an expired U.S. patent to Towner (1971) (U.S. Pat. No. 3,619,815).
Towner (1971), U.S. Pat. No. 3,619,815, represents the closest known prior art; however, substantial differences in use and function exist when compared to the present invention. Towner (1971) invented an “eyelid shield” that was “substantially opaque” to protect the eyes while “sunbathing” or for use by “outdoor workmen and others exposed to bright sunlight or overhead lighting”. Further, Towner's device was “domed” being “semi-ovate” and constructed of “thin plastic sheet material” that was attached to the eyelid by adhesive. Towner's device also had an integral “eyeshade” which was a “unilateral forwardly extending translucent portion shading the eyes when open” (page 1-2, U.S. Pat. No. 3,619,815). Towner (1971) makes no mention of use of this device for a sleep aid. Further, the device that Towner claims would be wholly inadequate as a sleep aid.
Worn sleep aids such as sleep masks and eyelid covers, as previously mentioned, must be extremely comfortable so as to not interfere with sleep. Towner's (1971) device is made of plastic, is in a semispherical construction, and includes an extended eyeshade. These three features preclude the use of this device for a sleep aid and his device is of questionable utility in general. Towner states that his device is made of plastic but able to fold into the ocular cavity atop of the eyelid. Plastic, even when thin, is not the most flexible material. It seems unlikely that the device could easily fold into the ocular cavity atop of the eyelid as Towner describes. Even if the device could fold as described, it would necessitate the use of a much stronger adhesive than if the device had been made of a superior, more flexible, material that would fold atop the eyelid in an easier manner. Further, once folded in the ocular cavity plastic is likely to return to its formed shape more readily than superior materials. This force to return to its formed original shape would create undue pressure on the top of the eyeball and ocular cavity tissue. (Please see FIG. 5 of Towner (1971)). Also, Towner's device is made of plastic which is unsuitable for a sleep aid. Plastic will prevent the eyelid skin from the contact with the air which will in turn cause heat and moisture buildup under the device. These unpleasant sensations are not conducive to sleep.
Towner's (1971) “domed” and “semi-ovate” semispherical construction is problematic for a sleep aid. When sleeping, various forces are placed on the face and eyelid by way of pressure of gravity from the head and face resting on the pillow (if someone is sleeping on their stomach or on their side). As such, these forces tend to distort the shape of the eyelid atop the eyeball into some other shape other than the usual semispherical shape. Towner's device would likely be very uncomfortable in these situations. Additionally, since Towner's invention is “domed” and “semi-ovate”, if part of it were to become depressed (such as from force exerted by the pillow) when the force was removed it would snap back to its original shape. This return to original shape would likely be accompanied by both a sound made by the plastic and a sensation of the skin of the eyelid being pulled. Both the sound and the pulling-skin-sensation would not be comfortable nor conducive to sleep. A further problem with a preformed “domed” “semi-ovate” shape is that everyone's eyeballs and eyelids are of a different size and shape. For example, if someone had larger or smaller eyelids the preformed size of Towner's device would not fit those individuals.
Towner's (1971) device has an extended eyeshade that protrudes from the front of the device. This eyeshade would contact the pillow while sleeping and either pull the eyelid cover off or exert pressure on the tissue around the eye. Again, Towner's device was not conceived for use as a sleep aid and would be unsuitable as such.
The fundamental safety of Towner's (1971) device, as conceived, or as used as a sleep aid is questionable. Towner describes the device as made of “thin plastic sheet material” (page 2; U.S. Pat. No. 3,619,815). Thin plastic has a thin, yet sharp, edge. For example, thin plastic is about the same thickness of thin paper. Paper can easily cut skin. Furthermore, the proximity of something that could cut skin being close to the eye is dangerous. Additionally, the eyeshade extension that Towner (1971) describes, or another part of the device, could bend back and cut the eyeball if force where exerted on it by a pillow while sleeping. Again, any edge of the device could cut the eye while someone was applying the device. A cut to the eyeball, face, or eyelid is highly dangerous and highly undesirable.
In summary, all prior inventions designed to help block light from the eye by way of entry through the eyelid suffer from some or all of the following disadvantages:
(a) They are expensive to manufacture. This cost prohibits the sale of these products to a wide variety of consumers.
(b) They are heavy. For example, light-blocking drapery liners can strain or damage curtain rod assemblies.
(c) Do to their size they are unable to be used while traveling. For example, the use of light-blocking drapery liners is prohibitive while traveling due to the unknown constraints of fitting the window in which the traveler finds himself/herself.
(d) They interfere with the sleep process due to their uncomfortable nature. For example, sleep masks invariably create a sensation of something that is covering the eyes or face. This can either be prohibitive due to pressure that is exerted on the eyes, face, or head of the wearer or through a psychological process of causing claustrophobia.
(e) They interfere with the sleep process because their usage is incompatible with the physiological necessities of sleep. For example, if one chooses to put on or take off eyelid covers or a sleep mask, these processes of putting on or taking off the device, would necessitate a certain amount of physiological arousal. In turn, this physiological arousal is likely to result in the person entering a more awake state from a formerly somnolent state—which is incompatible with sleep. Further, prior art sleep masks and eyelid covers present a problem in that one must be somewhat awake to put them on correctly. This is problematic if one wants to read before going to sleep and fall asleep without fiddling with the application of a sleep mask or eyelid cover. The actual application of a sleep mask or eyelid cover, after some preferred pre-sleep behavior such as reading, is likely to cause physiological arousal thereby being incompatible with sleep.
(f) They interfere with normal vision. Currently, all known prior inventions that are designed to be sleep aids when worn on the eyelid, face, or head interfere with normal vision. Towner (1971) is the lone exception, but his device was not conceived as a sleep aid. And, more importantly, for the previously discussed reasons, Towner's (1971) device is generally dangerous and wholly unsuitable as a sleep aid. The interference with normal vision and the special demands of sleeping are substantial. For example, sleep masks or various eyelid covers must be removed in order to see out of the eyes. The interference of normal vision is problematic because often the user would like to see instantly without engaging the process of removing the inventions from the eyelid, face, or head. For example, someone that is asleep may be awakened by a home intruder and instantly want use of their sight. Similarly, a soldier who is sleeping in a combat condition during the day, in extreme dessert sun, may want the benefits of a light-occluding device, but would not use the prior art due to the drawback of the inability to instantly have use of his/her sight. Further, all known prior art related to sleep aids prohibits normal vision. Therefore, one cannot read before going to sleep with prior art inventions and cannot instantly open his/her eyes to see something in the bedroom such as an alarm clock.
(g) They are of varying ability to actually block light from entering the eye through the eyelid. For example some sleep masks when worn do not fit the contours of the face and allow light to enter these spaces between the face and the mask.
(h) They are of non-adjustable ability to block light from entering the eye through the eyelid. For example, often an eyelid cover blocks all light or for U.S. Pat. No. 4,944,040 to Riedel and Olsen (1990) the eyelid cover blocks certain wavelengths of light. However, no known prior art blocks varying amounts of light. For example, no known prior art sleep masks or eyelid covers are designed to block 50 percent of light or 75 percent of light or 95 percent of light. Sometimes a consumer may want to wear an eyelid cover that blocks only 50 percent of light so awakening in the morning is more easy due to more light entering the eye through the eyelid. Conversely, another consumer may want to wear an eyelid cover that blocks 95 percent of light or higher so that he/she can sleep effectively in an intense light environment.
(i) They are dangerous and not conceived as a sleep aid. In particular, Towner's (1971) device is, as previously discussed, 1) generally dangerous, 2) not conceived as a sleep aid, and 3) incapable of being a sleep aid due to safety and comfort factors.